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This still needs a lot of cleanup, but wanted to put what I had up here for your perusal while I'm gone.
I just did that to get it to work temporarily without that `.js` class. I didn't mean for it to be a permanent thing. We need to ensure that users without JS can navigate to the second-level pages. We could let the second level remain hidden and force them to go through the landing pages for each section, but I think it's probably preferable if we just let the menu fall back to functioning via standard CSS and not sweat the extra stuff that the JS was doing.